We postulate that an important reason for failure of recovery of function after injury of the spinal cord is the formation of a scar made of polymerized collagen and dense connective tissue, forming a mechanical barrier for growth of axons. Although most investigators agree with this statement, so far nobody has been able to selectively and specifically inhibit scar formation or to prevent the development of dense scar. Our previous research on regulation of lysyl oxidase laid the foundation for our proposal. We propose to prevent the maturation of connective tissue, mainly collagen, by pharmacological interference, using a topically applied drug, beta-aminopropionitrill (BAPN), known to selectively and specifically block the polymerization of collagen. Another drug to be studied, D-penicillamine complexes the aldehydes involved in the formation of the crosslink in addition to inhibiting the lysyl oxidase. Both drugs will be delivered topically by sustained release from the Alza minipump or by controlled diffusion from silastic membrane device. At present, topical applications is preferred to systemic administration because of possible general toxicity of the drug. Several methods of delivering BAPN for a time period of 3-5 weeks will be studied in a dog model of spinal cord injury (SCI) after preliminary testing in a guinea pig model of peripheral nerve injury (PNI). By identifying methods for controlling the maturation of collagen in surgical wounds or other injuries and thereby preventing scar formation, information gained from the results of this study may help to prevent the lasting and severe damage to individuals suffering from injuries to the nerves and spinal cord.